Abdominal lymphadenopathy in benign diseases: sonographic detection and clinical significance.

We prospectively evaluated the frequency of lymphadenopathy in the right upper abdominal quadrant as detected by sonography in 650 consecutive unselected patients, after excluding patients with a known lymphoma or abdominal carcinoma and patients with acquired immunodeficiency disease. Evidence of enlarged lymph nodes (few in number, with an elongated shape and isoechoic to the liver, 8 to 22 mm in size), found primarily in the gastrohepatic ligament and porta hepatis, was seen on sonographic scans in 106 patients (16.3%). Associated conditions in 69 of 106 patients (65%) were hepatobiliary or pancreatic diseases and, less frequently, other benign entities (12 patients; 11.3%); in 25 cases (23.5%) no significant abdominal or systemic disease was present. Comparison with CT or surgical findings, or both, was available in 36 cases. We conclude that lymphadenopathy in the right upper abdominal quadrant may be found in relation to different non-neoplastic conditions as well as in the absence of any significant intra-abdominal disease. The frequency of this finding on sonographic scans must be recognized to prevent misdiagnosis of lymphoma or metastatic disease as well as to avoid overstaging of local (hepatobiliary, pancreatic, gastric) neoplasms.